In U.S. Pat. No. 6,090,130, which is assigned to Kensey Nash Corporation, a system for sealing a percutaneous puncture in a blood vessel is disclosed. For the determination of the position of the blood vessel, the system comprises a blood vessel locator, which, in turn, comprises an introducer sheath and a dilator. The position of the blood vessel is determined by observing a flow of blood out from a hole in the proximal end of the introducer sheath. The hole in the proximal end of the introducer sheath is via a canal in fluid communication with a hole in the distal end of the vessel locator. U.S. Pat. No. 6,090,130 discloses several different embodiments of how this canal and the distal hole can be arranged. A common requirement for these embodiments is, however, that the length of the dilator is adapted to the length of the introducer sheath.
U.S. Pat. No. 6,090,130 describes also a typical, conventional, intravascular surgical procedure, in which an introducer sheath according to the patent can be used. It is said that in such a procedure, a cannula of an instrument, such as an angiographic needle, is inserted percutaneously through the skin into the artery, such as the femoral artery, at the situs for the instrument's insertion. The needle cannula is held in place and the flexible end of a mini-guidewire is then passed through the cannula into the artery to the desired length. Once the mini-guide is in place, the needle cannula is removed, leaving the guidewire in place. An introducer sheath and an arterial dilator are then passed over the guidewire, through the puncture or incision and into the artery. The guidewire and then the dilator are removed, leaving the introducer sheath in place. A catheter, or other intravascular instrument, is then inserted through the introducer sheath and threaded down the artery to the desired intravascular location.
In the above description of the intravascular surgical procedure, which is taken directly from U.S. Pat. No. 6,090,130 and which is based on the so-called Seldinger technique, it is explicitly assumed (by reference numerals) that the introducer sheath being used during the intravascular procedure is the same introducer sheath as the introducer sheath into which a dilator is inserted when the intravascular operation has been completed and the sealing operation is to be performed. In other words, it is assumed that there is only one introducer sheath used during the whole medical operation, i.e. during both the actual intravascular procedure and the subsequent sealing operation. Although this could be the case, it is to the best of the present applicants' knowledge almost never actually the case. The reason for this is mainly that the needle cannula, introducer sheath, dilator, guide wire and catheter, and possibly some more instruments, come together in a separate set, which presumably is provided by another company than the company that provides the sealing system, i.e. in this particular example the Kensey Nash Corporation. Now, if the length of the special dilator, which is used to provide the canal in the vessel locator according to U.S. Pat. No. 6,090,130, does not match the length of the introducer sheath which already is inserted in the artery, this introducer sheath has to be replaced with an introducer sheath having the suitable, known length. Since introducer sheaths come in a variety of dimensions, the first introducer, which is inserted in the artery, must usually be replaced, and a special replacement technique has been developed for this purpose. In one stage, this known replacement technique requires that a medically trained person apply manual compression pressure, and the technique requires further that two separate instruments, a guide wire and a dilator, are used.